+# Start measuring dirty page rate of the VM. Results can be retrieved
+# with @query-dirty-rate after measurements are completed.
+#
+# Dirty page rate is the number of pages changed in a given time
+# period expressed in MiB/s. The following methods of calculation are
+# available:
+#
+# 1. In page sampling mode, a random subset of pages are selected and
+# hashed twice: once at the beginning of measurement time period,
+# and once again at the end. If two hashes for some page are
+# different, the page is counted as changed. Since this method
+# relies on sampling and hashing, calculated dirty page rate is
+# only an estimate of its true value. Increasing @sample-pages
+# improves estimation quality at the cost of higher computational
+# overhead.
+#
+# 2. Dirty bitmap mode captures writes to memory (for example by
+# temporarily revoking write access to all pages) and counting page
+# faults. Information about modified pages is collected into a
+# bitmap, where each bit corresponds to one guest page. This mode
+# requires that KVM accelerator property "dirty-ring-size" is *not*
+# set.
+#
+# 3. Dirty ring mode is similar to dirty bitmap mode, but the
+# information about modified pages is collected into ring buffer.
+# This mode tracks page modification per each vCPU separately. It
+# requires that KVM accelerator property "dirty-ring-size" is set.
+#
+# @calc-time: time period for which dirty page rate is calculated.
+# By default it is specified in seconds, but the unit can be set
+# explicitly with @calc-time-unit. Note that larger @calc-time
+# values will typically result in smaller dirty page rates because
+# page dirtying is a one-time event. Once some page is counted
+# as dirty during @calc-time period, further writes to this page
+# will not increase dirty page rate anymore.
+#
+# @calc-time-unit: time unit in which @calc-time is specified.
+# By default it is seconds. (Since 8.2)
+#
+# @sample-pages: number of sampled pages per each GiB of guest memory.
+# Default value is 512. For 4KiB guest pages this corresponds to
+# sampling ratio of 0.2%. This argument is used only in page
+# sampling mode. (Since 6.1)
+#
+# @mode: mechanism for tracking dirty pages. Default value is
+# 'page-sampling'. Others are 'dirty-bitmap' and 'dirty-ring'.
+# (Since 6.1)